Process of manufacturing spongy lead.



the powdering,

Patented August 16, 1904.

JIILIEN HENRI MERCADIER, OF LOUVRES, FRANCE.

PROCESS OF MANUFACTURING SPONGY LEAD..

SPECIFICATION forming part of Letters Patent N0. 767,906, dated August16, 1904. Application filed April 2, 1904. Serial No. 201,389. (Nospecimens.)

To all whmn it may concern:

Be it known that I, J ULIEN HENRI MEROA- DIER, curate, a citizen of theRepublic of France, residing at Louvres, Seine-et-Oise, in the Republicof France, have invented certain new and useful Improvements inProcesses of Manufacturing Spongy Lead, of which the following is aspecification.

This invention relates to a process for manufacturing spongy leadspecially intended for the construction of electric accumulators, butwhich may also be used for any other manufacturingpurpose, such as thepurification of oils, &c.

This novel process consists in incorporating in a suitable manner asuitable metal oxid with molten lead when the latter is cooling. Themode of operation is as follows: A certain quantity of molten leadislocated in a receptacle and then gently stirred by means of an ironfo'rkf0r instance, one preferably grown rustyor a wooden fork or thelike. This stirringis for the purpose of preventing the lead fromthickening on and sticking to the walls of the receptacle. At the sametime that the stirred lead is cooling it is powdered, and especiallynear the edges of the receptacle, with a metal oxid, such as litharge orminium or oxid of Zinc or a mixture of these oxids. For certainapplications other metal oxids and even ashes may be used. When the leadbegins to become pasty, the receptacle is placed over a slight flame,and then begins the most important stage of the process of manufacture.During the whole of this stage the pasty mass of lead is stirred or,better still, kneaded by means of the stirrer, while the lead is beingcontinuously powdered with the oxid or a mixture of oxids, which islocated for that purpose in a box pierced with holes. The pasty leadthus closely mixed with the oxid cannot solidify in a compact mass. Ifthe operation has been well performed, including there is obtained whensolidification has taken place a lump or mass of lead full of aninfinite number of cavities and of veins, which render it extremelyspongiose and capable of being rapidly penetrated by aquae acidulae. Thelead is not in a state of powder, but of filaments, which are solderedtogether in leaving interstices between them. The lump of spongy leadthus obtained is so resisting that it does not become disaggregated evenunder the action of a rolling-mill. It can be put in the form of platesto serve as accumulator-plates, and in this case the use of an armatureof ordinary or hardened lead is not necessary to give to the plates therequired rigidity, for the spongy lead is sufficiently strong of itself.

In the preparation of the novel product in the manner described when theaddition of oxid and the kneading are thought to be sufiicient thematter is thrown quite hot into a mold in order to give it the desiredshape or form.

If solidification comes on before the knead-.

ing is over, one has only to increase the intensity of the-flame underthe receptacle to again reduce the lead into a fluid state, and then themixing and the kneading are progressively continued and completed.

In the application to electric accumulators the plates of spongy leadobtained by the present process do not require a long preparation andcan be used almost immediately on being taken out of the mold, whilegiving at the same time excellent results, for the oxids which areformed within the mass of the plates are well maintained and do notbecome disaggregated.

I claim 1. A process for the manufacture of spongy or porous lead,consisting in incorporating metal oxids with the lead when in a pastystate by powdering and kneading.

2. A process for the manufacture of spongy or porous lead, consisting inreducing lead to a liquid state by heating, in allowing it to coolgently, in continuously kneading and powdering the lead with a metaloxid while cooling.

3. The process of manufacturing spongy lead, consisting in incorporatingmetallic oxid with lead while the latter is in a state of fusion.

4. The herein-described product resulting from the incorporation ofmetallic oxid with lead while the latter is in a state of fusion.

In testimony that I claim the foregoing as my invention I have signed myname in presence of two subscribing witnesses.

JULIEN HENRI MERCADIER.

Witnesses:

CAMILLE DUBOIS, MAURICE Roux.

